While mandatory evacuation orders were rescinded shortly before 6 p.m., voluntary evacuations remained in effect for residents north of Hillside Road between Hermosa and Haven avenues, and North of Banyan Street between Haven and Milliken avenues, according to a statement from Rancho Cucamonga city officials.

By late Wednesday, the wind-driven wildfire, which is believed to have started around 8 a.m. near Day Canyon, had consumed more than 1,000 acres, disrupted air travel at L.A./Ontario International Airport and prompted school closures, while no containment had been announced.

The cause of the fire remains under investigation. San Bernardino County sheriff’s spokeswoman Teresa McMahon said.